That's weird, so it was behaving fine before the trip, and nothing was done to the car (mods, repairs, whatever) before the problem started? Do you still have the stock purge valve (I assume FD's have one) plumbed in correctly? Link to a FC version of this part for ref:
https://www.atkinsrotary.com/store/7...tegory_id=1060
Maybe posting up some detailed pictures or a diagram showing exactly how the catch can is plumbed into the engine would help figure this out.
Also, regarding the fuel in the catch can, do you still have the factory charcoal canister and its associated plumbing intact?